1. Field of the Invention
The present invention relates to a sheet conveyance apparatus and a recording apparatus that records an image on a sheet.
2. Description of the Related Art
Japanese Patent Application Laid-Open No. 2004-323149 discusses a paper conveyance apparatus and an image forming apparatus that use a conveyance roller pair that includes at least one split roller in which the roller portion is split. By applying a biasing force on one of the conveyance rollers from the split roller, a compressive force can be uniformly applied without causing the conveyance rollers to go slack. Further, the paper orientation is corrected by a film guide provided on an upstream side that presses the sheet. Consequently, the sheet is conveyed in a flat shape, which prevents the wrinkles that are produced by the sheet bending between the split rollers. The orientation of the entire sheet width is corrected by the film guide before the sheet is fed from the upstream side to the roller pair, whose configuration includes a drive roller and a driven roller that is split from the drive roller.
However, in a sheet conveyance apparatus like that discussed in Japanese Patent Application Laid-Open No. 2004-323149, which presses the sheet with a film, the pressing force of the film on the sheet causes a back tension to act on the conveyance roller pair arranged on a downstream side. Consequently, there is the problem that the actual conveyance distance is shorter than an ideal conveyance distance.
Further, the back tension becomes uneven due to changes in the rigidity of the film member resulting from wear of the film caused by friction with the conveyed sheet and changes in the humidity and temperature environment. Consequently, there is greater unevenness in the actual conveyance distance with respect to the ideal conveyance distance, so that such a configuration is not suited to high precision conveyance.
In addition, employing a configuration that presses a film against the sheet can cause problems such as peeling or bending of the film due to an increased load on the fixed face of the film.